1. Field of the Invention
The present invention relates to a verification or examination system, method, program and storage medium on which the verification or examination program is stored. More particularly, the present invention relates to a system and method for verifying or examining distances within electrical systems and their respective components without producing actual electrical system prototypes.
2. Description of the Related Art
It is typical to conduct safety checks on prototype systems before the actual systems are manufactured. Conventionally, a prototype system is actually produced and tested to determine whether it has a problem.
For example, in components and/or interconnection wires to which electric voltages are applied, the distances among components and/or interconnection wires should be large enough to accommodate the required insulation. The produced prototype system is broken down into components, and voltage systems including components to which voltages are applied are analyzed. Lengths of shortest paths among electrically conductive parts in voltage systems along surfaces of components are manually measured using a measuring tool such as a vernier caliper, and the measured lengths are evaluated to determine whether they are large enough to accommodate the required insulation.
However, with this method, testing is possible only after the prototype system is produced. If a problem is detected, the system must then be redesigned, and a prototype produced and evaluated again in a similar manner. Such design, testing and redesign iterations can become costly and consume valuable resources such as time and materials.
Moreover, this process is prone to errors since the process is performed by a human designer, who analyzes and measures the voltage systems, so that there is a possibility that an incorrect path is selected and measured. Further, in some cases, an inner part of a component of a produced prototype system cannot be measured when measurement of that part is essential.
An alternative method is to use design data to determine the distance between two particular points and determine whether this distance is large enough to accommodate the required insulation.
In the art of computational geometry, several computational techniques are known for determining the shortest path between two points along a surface of a single triangular polyhedron.
However, when the distance between two points on a high-order curved surface of an object is to be determined, the shortest path along trimmed patches expressed by a plurality of equations is determined, which requires that an optimization problem for a plurality of high-order objective functions be solved. Solutions to these high-order objective functions can be difficult to obtain and no computational method is known for quickly solving these functions.
One known method of determining the distance along a surface of a simple triangular face polyhedron is to develop the surface of the polyhedron into a plane and determine the exact distance in the developed plane. Another known method is to find the shortest path using a discretely weighted approximate graph.
However, in the method of determining an exact distance in a developed plane, it is difficult to quickly obtain a solution for a polyhedron with many surfaces. In particular, no quick method is known for determining the shortest path along object surfaces, and no quick method is known for determining a creepage distance between voltage systems. It is unknown to optimize the solving process for the insulation distance problem. For example, optimization is unknown for the case in which determination of the simple creepage distance is insufficient and a spark in a spatial gap (or a park through a connection part) must be taken into account.
An example of a spark through a small spatial gap between two components is shown in FIG. 17. In this example, two components 1701 and 1702 are placed on a plane 1704 such that they are spaced apart from each other by a small gap 1703. A high voltage is then applied between the component 1701 and the plane 1704. In this structure, a spark can occur directly or indirectly between the component 1701 and the plane 1704. The indirect path extends partially along the surface of the component 1701, through the small gap 1703 to the component 1702 and then along the surface of the component 1702 to the plane 1704. In this case, the path of the spark depends on the material of the component 1703.
FIG. 18 shows an example of a spark occurring through a component. In this example, components 1801 and 1802 are in contact with each other, and a high voltage is applied between a particular part of the component 1801 and a vertex 1803 of the component 1802. In this case, depending on the material of the component 1802, the shortest path between the component 1801 and the vertex 1803 is not along the surfaces of the components 1801 and 1802 but can be through a part of the component 1802, and a spark or a leakage can occur through such a path through the component 1802.
Even one skilled in the art may have some difficulty based on the above. The skilled individual has to calculate a simple creepage distance, and then simulate the occurrence of spark or leakage through a gap or connection part. Even if the possibility of a spark is predicted, it may be difficult to predict an exact path for the spark. And, the skilled person must then determine distances, for example, insulation distances, between such components. Not only can these difficulties result in errors, they can result in loss of valuable resources such as time and material.